Mother-of-pearl from the shells of Akoya Pearl Oysters has long been valued in Japan for decorative inlay, but until recently pearls held little appeal for the Japanese. Akoya pearls became popular in Japan only after they began to be cultured for export in the 1920s. By the 1950s, Akoya pearls had won widespread popularity. The single strand of pearls soon became an essential for the well-dressed woman in Japan, the United States and Europe.